Molded foams are typically obtained by causing a resin composition to foam, and can be reduced in weight and cost and made resistant to heat. Molded foams are therefore used in various applications such as food containers, daily necessities, and home appliances. Especially for use in applications such as food containers, molded foams are desired to have sufficient heat resistance for heating in a microwave, for example. In addition, environmentally friendly molded foams have drawn attention, and molded foams obtained by foaming of a resin composition containing a mixture of a polyolefin and a polylactic acid, for example, have been studied.
For example, Patent Literature 1 discloses a polylactic acid foam of beautiful appearance excelling in heat resistance and having satisfactory mechanical properties obtained by blending polylactic acid, a polyolefin resin, and a vinyl-carboxylate-modified polyolefin resin at a certain ratio. Patent Literature 2 discloses a molded foam having high softness, high flexibility, and excellent foamed cell state obtained by foam molding, with a foaming agent, a resin composition containing an aliphatic polyester, a polyolefin, and a functional group-containing hydrogenated diene polymer.